The use of switches in electrical circuits associated with machinery and other equipment are known in the art. Switches such as circuit breakers typically control the flow of electrical current and may take the form of a toggle switch with a lever that is manually operated between the ON and OFF positions to complete or interrupt the electrical circuit. Such switches are frequently placed in protective enclosures when used in explosive atmospheres (i.e., an environment containing flammable vapors) or otherwise harsh environments. Protective enclosures provide a measure of safety, i.e., by creating a barrier between flaming gases and the personnel operating the switches.
For switches housed in an enclosure, a remote operating device may be utilized to penetrate the enclosure walls and allow the switches to be externally operated. This is often the case for explosion-proof or hazardous location-related enclosures in which an externally operated switch may be required.
Prior art remote operators, however, are limited in their function. They are only capable of turning ON or OFF a single corresponding switch per remote operator. However, in practice, circuits may have coupled thereto a plurality of switches such as a circuit breaker, fault test initiators and so forth. Given the limitations of current remote operators, the additional switches associated with the circuits must either be operated by a person from an internal position in the enclosure (i.e., opening the panel and operating the switch), or a separate remote operator must be incorporated into the enclosure for those additional switches. For the former case, the internal operation of a switch is impractical and especially dangerous for explosion-proof or hazardous location-related enclosures, as described above. For the latter case, the incorporation of additional remote operators into the enclosure increases the overall cost of the system and, more importantly, decreases the overall integrity of the enclosure by requiring additional holes to be drilled into the enclosure.
Accordingly, there is a desire to provide a remote operator that is capable of functioning to operate a toggle switch in a circuit breaker or the like, and concomitantly therewith a push to test switch.
Other problems associated with prior art remote operators also involve the misalignment of the remote operator with respect to the toggle lever, when the panel of the enclosure is in the closed position. For example, during product assembly, installation and maintenance, the door must be opened and the remote operator disengaged with the circuit breaker in either the ON or OFF position. Reclosing the door with a misaligned operator prevents the operator from engaging the breaker toggle, leaving the circuit breaker inoperable. Moreover, the occurrence of a misalignment may not be apparent, particularly in light of the fact that the door is in the closed position thereby preventing a view of the operator and switch.
In addition, misalignment is typically remedied by painstakingly guiding the operator onto a toggle lever (for actuating a switch) as the door closes. This task is performed blindly, requiring the person making the adjustment to do so with the enclosure door closed (i.e., not seeing how the operator mates with the toggle lever).
One approach to remedy the above problem is to employ a remote, self-adjusting operator as disclosed in U.S. Pat. No. 5,286,935 to Mina et al. and U.S. Pat. No. 5,577,603 to Bogdanovs et al. Both remote operators automatically move into an aligned position with respect to the toggle lever, when the door to the enclosure is closed. Such devices do not provide or require an indication of a misalignment.
There is a desire to provide an alternative approach to the misalignment problem in which a circuit operator is capable of indicating a misalignment of the circuit operator with respect to the toggle lever, when the door of the enclosure is in the closed position. There is also a desire to provide a circuit operator that provides a safe and easy method for realigning the circuit operator with the toggle lever when the door of the enclosure is in the closed position.
In view of the foregoing, it is an object of the present invention to provide a circuit operator that is capable of externally operating multiple switches, i.e., a circuit breaker and fault test switch, maintained in a housing.
It is a further object of the invention to construct the above circuit operator such that fewer holes need to be drilled in the housing, thereby proving a stronger housing that requires less materials and reduces the assembly time of the overall device.
Another object of the invention is to provide a misalignment indicator which indicates a misalignment of a switch actuator, when a cover of the housing is in the closed position.
It is still yet a further object of the invention to provide a circuit operator that provides a simple, easy method for realigning the switch actuator, when an openable cover of the housing is in the closed position.